Canon EOS-1D: Fix for banding problems! (UPDATED)
By
Mike Tomkins
(Friday, February 1, 2002 - 04:00 EST)
Japanese camera manufacturer releases firmware, tone curves to correct the much-discussed issue of horizontal banding in images...
Canon Japan has today released a firmware update and two new tone-curves for its EOS-1D professional single-lens reflex digital camera. Version 1.2.0 of firmware, available from Canon's BeBit website, is aimed at correcting issues that some users have reported (and which have been much-discussed in forums around the 'Net) where areas of darkness in high-ISO images can show vertical banding.
Canon says that the problem occurs because "[the] EOS-1D's image processing is designed to make use of the image sensor's high-quality gradation in order to reproduce dark subjects and backgrounds faithfully. When higher ISO speeds are used, however, a visible noise pattern may appear in certain images according to the scene." The company notes that the firmware update alone is enough to significantly alleviate this issue, however it also recommends the use of one or other of its new tone curves which adjust the color density and brightness of the image, and are tuned for noise reduction.
The two tone curves have differing levels of effect on the banding problem - one being aimed at reducing noise whilst still retaining dynamic range, whilst the other reduces noise even further but narrows dynamic range somewhat. When the tone curves are used and an ISO rating from 200 to 3200 is selected, the effective ISO rating of the camera is reduced by 1/3 or 2/3 step (depending on which curve is used), and either a 1/3 or 2/3EV step of positive exposure compensation will need to be dialed in.
Full instructions on how to install the firmware update and how to use the tone curves are available on the BeBit website, and are outside of the scope of this news item. That said, be sure to follow the instructions for the firmware upgrade carefully - not following the correct procedure can conceivably result in damage that will require the camera to be returned to a service center for repair.
UPDATED 2002-02-01 23:43ET: At the moment, we're aware of two EOS-1D users who've kindly posted before/after comparison images to show what results they've had with the firmware upgrade and tone curves. Adam Tow has a page with 600 x 600 pixel crops from ISO 1600 images taken before and after the firmware upgrade. The "after" section has both the results with only the new firmware, and with a combination of the new firmware and tone curve.
The second site we're aware of is W.S. Lam's EOS-1D Tests page. W.S. has posted ~ 600 x 233 pixel before and after crops at both ISO 200 and 1600, along with a comparison for reference with the Nikon D1x digital camera at ISO 1600.
On behalf of the EOS-1D community, our thanks to both Adam and W.S. for taking the time to share their results with other 1D owners...
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